1. Field of the Invention
The present invention relates to an image forming system for forming an image on a recording sheet, coated with a layer of micro-capsules filled with dye or ink, by selectively breaking or squashing the micro-capsules in the layer of micro-capsules. Further, the present invention relates to such a recording sheet and an image-forming apparatus, which forms an image on the recording sheet, used in the image-forming system.
2. Description of the Related Art
An image-forming system per se is known, and uses a recording sheet coated with a layer of micro-capsules filled with dye or ink, on which an image is formed by selectively breaking or squashing micro-capsules in the layer of micro-capsules.
For example, in a conventional image-forming system using a recording sheet coated with a layer of micro-capsules in which a shell wall of each micro-capsule is formed from a photo-setting resin, an optical image is formed as a latent image on micro-capsules by exposing it to light rays in accordance with image-pixel signals. Then, the latent image is developed by exerting pressure on the layer of micro-capsules. Namely, the micro-capsules, which are not exposed to the light rays, are broken and squashed, whereby dye or ink seeps out of the broken and squashed micro-capsules, and thus the latent image is visually developed by the seepage of dye or ink.
Of course, in this conventional image-forming system, each recording sheet must be packed so as to be protected from being exposed to light, resulting in wastage of materials. Further, the recording sheets must be handled such that they are not subjected to excess pressure due to the softness of unexposed micro-capsules, resulting in an undesired seepage of dye or ink.
Also, a color-image-forming system, using a recording sheet coated with a layer of micro-capsules filled with different color dye or ink, is known. In this system, the respective different colors are selectively developed on a recording sheet by applying specific temperatures to the layer of color micro-capsules. Nevertheless, it is necessary to fix a developed color by irradiation, using a light of a specific wavelength. Accordingly, this color-image-forming system is costly, because an additional irradiation apparatus for the fixing of a developed color is needed, and electric power consumption is increased due to the additional irradiation apparatus. Also, since a heating process for the color development and an irradiation process for the fixing of a developed color must be carried out with respect to each color, this hinders a quick formation of a color image on the color-recording sheet.